“There are some prominent members of the Republican Party who have articulated their support for articles of impeachment,” Mr. Earnest said at his daily briefing. “What we’re focused on is the business of the American people.”

It might not even be too strong to say that Democrats love all the talk of impeachment, even if the most prominent Republican to beat that drum is former vice-presidential nominee Sarah Palin.

Or perhaps it’s especially because Ms. Palin is leading the charge that Democrats are gleeful. She’s the perfect foil. Now several years out of elective office, the ex-governor of Alaska and tea party rabble-rouser still knows how to grab headlines. And when she brings up the “I-word,” you can be sure a Democratic fundraising e-mail isn’t far behind.

Less than four months before the November midterms, Palin’s impeachment talk is a gift to Democrats. And it’s not just about money: It’s also about turnout. Democrats are famous for not voting in midterms as reliably as Republicans.

Pfeiffer mentioned a CNN/ORC poll that came out Friday showing that 35 percent of Americans support the impeachment of Mr. Obama, while 57 percent of Republicans do. Pfeiffer even put a timeline on possible impeachment: after Obama takes executive action on immigration, which the aide said would come after the summer.

“I think that the president acting on immigration reform will certainly up the likelihood that they would contemplate impeachment at some point,” he said.

Pfeiffer’s comments also created fodder for Democratic fundraising e-mails on impeachment.

“This is an all-hands-on-deck moment,” said an e-mail from the Democratic Congressional Campaign Committee. “A top White House official just said that ‘Speaker Boehner ... has opened the door to impeachment ....’ "

Never mind that Boehner and other establishment Republicans know that an effort to impeach Obama would almost surely backfire. Right after House Republicans impeached President Clinton in December 1998 for perjury and obstruction of justice, his job approval rating shot up 10 percentage points to 73 percent in the Gallup poll.

It was an all-time high for Mr. Clinton’s presidency, and one of the higher job approval ratings of any US president since the mid-1960s, according to Gallup.

Clinton had also just launched airstrikes against Iraq and its leader, Saddam Hussein, a popular move. But there’s no doubt that the House vote for impeachment also boosted Clinton’s stock. Only 31 percent of those polled said the Senate should proceed with a trial. Two months later, Clinton was easily acquitted in the Senate.

Fast-forward to today. Will Republican backbenchers in the House, many of them elected with tea party support, keep up the talk of impeachment, despite the history? Not if their party elders have a say.

“We are not working on or drawing up articles of impeachment,” House Judiciary Committee chairman Robert Goodlatte (R) of Virginia said July 13 on ABC News’s “This Week.” “The Constitution is very clear as to what constitutes grounds for impeachment of the president of the United States. He has not committed the kind of criminal acts that call for that.”

But Boehner’s lawsuit is a different matter. On Thursday, the House Rules Committee approved a resolution backing the suit over Obama’s delay of the employer mandate in the Affordable Care Act. Republicans say the president overstepped his constitutional authority. The full House is expected to take up the measure before its August recess.